We were shooting some sort of Mexican field gun... never heard of it before, so I don't recall all the details.
The one to the right.. heck if I know... maybe one of the experts here can tell you. I do know that the one to the right used a detachable tubular sight (non-optical) with vernier adjustments on it. It was fired by "Lydia", the AAA club secretary who can be seen to the right in the first picture. She told me she has been shooting cannons for about 30 years, which would probably have been when she was about 5 years old.
The canister worked good for us... I beleve we one the canister competition. The owner of the gun had figured out how to hold the shot together untill about 10 yards before the target, but it separated reliably on all three shots. Other teams either had it open up way too soon or go thru as one solid projectile.